Project Abstract The goal of this application for a K23 Mentored Patient-Oriented Research Career Award is to prepare the candidate, Lauren Fisher, Ph.D., for a career in patient-oriented research focusing on traumatic brain injury (TBI) and major depressive disorder (MDD). This is an area of enormous public health importance, as depression occurs in about 50% of individuals who have sustained a TBI, leading to high rates of long-term disability and significantly impeding recovery and rehabilitation. The training goals of this career development award are for the candidate to 1) acquire expertise in MDD in individuals with moderate to severe TBI, which includes greater understanding of the neurobiology of TBI; assessment of depression in TBI; assessment of neuropsychological functioning; and 2) become highly proficient in cognitive behavioral treatment development, which includes tailoring treatment to the needs of the population; developing advanced skills in biostatistics; and training in the responsible conduct of research. The stated objectives will be achieved through: 1) Resources at Massachusetts General Hospital, Spaulding Rehabilitation Network, and Harvard Medical School (HMS); 2) Expert mentorship from researchers in the Departments of Physical Medicine & Rehabilitation (Primary Mentor: Ross Zafonte, DO; Co-Mentor: Grant Iverson, PhD; Consultant: Denise Ambrosi, MS, CCC- SLP) and Psychiatry (Co-Mentors: Maurizio Fava, MD, Paola Pedrelli, PhD; Consultants: Kalo Tanev, MD, Lee Baer, PhD) at HMS, as well as the Department of Rehabilitation Medicine at the University of Washington School of Medicine (Consultant: Charles Bombardier, PhD); 3) Targeted advanced coursework, seminars as well as supervised clinical experiences; and 4) Implementation of the proposed research project. The research component of this project will result in the development of a manualized cognitive behavioral intervention for MDD that has been adapted to account for the cognitive sequelae of TBI. The primary aims will be to develop the treatment manual following consultation with expert mentors and utilizing input from subjects and investigate the acceptability and tolerability of the intervention. Secondary aims will be to pilot test its potential efficacy for improving depression in patients with moderate to severe TBI and explore potential moderators and mediators of its effect. Results of this project will form the basis of an R01 grant application and will lay the foundation for a career-long research program focused on developing treatment protocols for depression after TBI and other neurological disorders. The candidate has demonstrated a strong commitment to a research career and excellence in her clinical and academic endeavors thus far. This research and training program will assist Dr. Fisher in making the transition to independent investigator and becoming an expert in rehabilitation psychology in an area with significant need and broad public health applications: the treatment of depression among individuals with TBI.